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<p class="MsoNormal"><span lang="en-DE">Hi Magnus,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="en-DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="en-DE">></span><span lang="en-DE"> </span>I think there might be ways around that to tell the linker to actually keep the symbols we need. If you want to pursue integrating msan into the JDK build properly, we can explore that.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am still a bit unsure about integrating the msan support , because with just the msan support in the m4+makefiles , but still msan-related runtime issues showing up in the build,<o:p></o:p></p>
<p class="MsoNormal">It would not be very helpful for the developers.<o:p></o:p></p>
<p class="MsoNormal">(on the other hand, ubsan in OpenJDK was some months ago also only supported in the m4+makefiles but needed ‘repair’ regarding source adjustments because issues already showed up in the build )
<span lang="en-DE"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="en-DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="en-DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="en-DE">>>Seems msan is unhappy about the thread != nullptr in line 81 of jfrThreadLocal.cpp</span><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">>I have no idea. Did you pursue this any further, or did you give up?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="en-DE">I updated to a higher version of clang (17) and then the issue was gone ; but unfortunately there are more msan – related issues reported in Hotspot already in the build process .<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="en-DE">And different to ubsan/asan , for me the msan issues are harder to understand (but maybe I am just not used to the reports yet ) .<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="en-DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="en-DE">Maybe , let’s see what comes out of this one
<a href="https://bugs.openjdk.org/browse/JDK-8356285">https://bugs.openjdk.org/browse/JDK-8356285</a> .<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="en-DE">(sometimes the HS codebase seem to does things that are not liked by MSAN ; maybe the JDK native libs are easier to support for MSAN )<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="en-DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="en-DE">Best regards, Matthias<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="en-DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="en-DE"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US" style="font-family:"Calibri",sans-serif;mso-ligatures:none;mso-fareast-language:#2000">From:</span></b><span lang="EN-US" style="font-family:"Calibri",sans-serif;mso-ligatures:none;mso-fareast-language:#2000"> Magnus
Ihse Bursie <magnus.ihse.bursie@oracle.com> <br>
<b>Sent:</b> Thursday, 19 June 2025 17:07<br>
<b>To:</b> Baesken, Matthias <matthias.baesken@sap.com>; build-dev@openjdk.org<br>
<b>Subject:</b> Re: clang Memory sanitizer (msan) and OpenJDK<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p>Hi Matthias,<o:p></o:p></p>
<p>Getting back to this far too late... Sorry.<o:p></o:p></p>
<p>On 2025-04-30 15:28, Baesken, Matthias wrote:<o:p></o:p></p>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal"><span lang="en-DE">I installed the llvm package to get the /usr/bin/llvm-symbolizer (this seems to be needed to get meaningful stacks) .<br>
<br>
Brought back the visibility=hidden settings, seems they do no harm to msan . However the removal of -Wl,--exclude-libs,ALL is needed.</span><o:p></o:p></p>
</blockquote>
<p>I think there might be ways around that to tell the linker to actually keep the symbols we need. If you want to pursue integrating msan into the JDK build properly, we can explore that. If so, we should also check for the presence of llvm-symbolizer in configure
and warn if it is missing (though I guess the real question is if it is present at runtime...).<o:p></o:p></p>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal"><span lang="en-DE"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="en-DE">Seems msan is unhappy about the thread != nullptr in line 81 of jfrThreadLocal.cpp</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="en-DE"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="en-DE"> Thread* thread = Thread::current_or_null();</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="en-DE"> _parent_trace_id = thread != nullptr ? jvm_thread_id(thread) : (traceid)0;</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="en-DE"> </span><o:p></o:p></p>
<p class="MsoNormal"><span lang="en-DE">Not sure why this is reported as uninitialized ?</span><o:p></o:p></p>
</blockquote>
<p>I have no idea.<o:p></o:p></p>
<p>Did you pursue this any further, or did you give up?<o:p></o:p></p>
<p>/Magnus<o:p></o:p></p>
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